[R] removing observations

[Peter Dalgaard]

"Justin G. Gardner" <jggardne at uiuc.edu> writes:

> Hello R list.
> 
> I am sure this is an easy question, please forgive my 
> ignorance of R.
> 
> 
> I have a panel data set (25 years) and I would like to break 
> it up by year, and run a few tests.  How is this done in R?  
> In STATA it is quite simple (keep if year =1970).  If someone 
> could give me an example of how to do it for a single year I 
> am sure I could make a little loop to do it for all 25.


There are multiple answers, mostly involving the subset(), tapply(),
or by() functions. So use help(subset), etc.

-- 
   O__  ---- Peter Dalgaard             Blegdamsvej 3  
  c/ /'_ --- Dept. of Biostatistics     2200 Cph. N   
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